ABSTRACT
Objective: To isolate and characterize the endophytic fungi from the leaves of Andrographis paniculata for free radical scavenging antioxidant and hepatoprotective activity against CCl4 induced hepatotoxicity Methods: Two fungal endophytes, APLF-3 (Andrographis paniculata leaf fungi-3) and APLF-4 (Andrographis paniculata leaf fungi-4) were isolated from leaves of Andrographis paniculata to get chloroform (A3C, A4C), ethyl acetate (A3EA, A4EA) and n butanol (A3nB, A4nB) extracts. rDNA sequencing by PCR technique was carried out for identification of APLF-3 and APLF-4. All the APLF-3 and APLF-4 extracts were assayed for in vitro free radical scavenging activity against 2, 2-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl radical and reducing power. Then, A4EA and A4nB were screened for hepatoprotective activity against CCl4 induced hepatotoxicity at 50 mg/kg and100 mg/kg doses. Results: The endophytic fungi, APLF-3 and APLF-4, were identified as Phyllosticta sp. ZLY-2010 isolate M13 and Aspergillus tubingensis strain Cs/7/2 respectively based on their morphological and molecular characterization. A4EA and A4nB showed significant in vitro free radical scavenging activity as compared to other extracts. A4EA and A4nB (50 mg/kg and100 mg/kg) reversed the increased serum biochemical parameters as compared to CCl4 treated group (p<0.001). A4EA and A4nB (100 mg/kg p. o) also restored the LPO, SOD and CAT levels. Conclusion: These findings suggested that the extracts (A4EA and A4nB) obtained from endophytic fungi APLF-4 contributed towards hepatoprotective activity.
ABSTRACT
Argyreia speciosa (sweet) (Burm.f.) Boj. is an Ayurvedic rasayana plant used as an adaptogen. The present study reports the investigations done on the adaptogenic property of ethanol (EtAS; 100 and 200 mg/kg; po), ethyl acetate (EAAS; 100 and 200 mg/kg; po) fraction and flavanoids such as quercetin and kaempferol (25 mg/kg; po) of the root. Immobilization induced acute stress (AS; 3 days) and chronic stress (CS; 7 days) and swimming induced stress models were used to screen the anti-stress effect of the plant fractions and isolated flavanoids. The tested doses of EtAS and isolated flavanoids were able to produce significant effects in normalizing altered serum biochemical parameters and the severity of ulcer in both AS and CS models. Higher dose of EtAS, quercetin and kaempferol (25 mg/kg; po) were found to be significant in restoring the hypertrophy of adrenal gland and atrophy of spleen and thymus gland only in CS model. Greater swimming time was noted in the mice pretreated with tested doses of flavanoids and EtAS. In addition, levels of adrenal ascorbic acid and cortisol were restored compared to stress control group. EtAS exhibited significant scavenging effect of DPPH, hydroxyl radical and LPO. Thus, EtAS, quercetin and kaempferol are capable of increasing the capacity to tolerate non-specific stress in experimental animals, as evident from restoration of large number of parameters in the stress models studied. Bioactivity of EtAS may be due to the synergetic action of isolated flavanoids. Improvement in stress markers may be due its prolong effect of resistance to stress and partly due to free radical scavenging activity.
ABSTRACT
Antimicrobial activity of flavanoid sulphates and different fractions of A. speciosa root was studied against bacteria, fungi and Mycobacterium tuberculosis H37 Rv sensitive strain by in vitro and in vivo assays. Flavanoid sulphates such as quercetin 3'7 di-O methyl 3- sulphate and kaempferol 7-O methyl 3-sulphate were isolated from the n-butanol fraction of 80% methanolic extract of the plant. The structures of the isolated flavanoids were confirmed by spectral studies. Ethyl acetate (EAAS) fraction and flavanoid sulphates inhibited the growth of M. tuberculosis Rv sensitive strain at MIC values 50 and 25 microg/ml, respectively. Ethanolic fraction (EtAS) showed significant inhibition of gram positive organism with a MIC of 31.25 microg/ml. More inhibition was observed with a less MIC (2 microg/ml) for flavanoid sulphates against Klebsiella pneumoniae, a gram negative organism and it is almost comparable with the standards. Interestingly, chloroform fraction alone exhibited significant antifungal activity with a MIC of 100 microg/ml. A synergistic effect between flavanoids sulphates and commercially available antitubercular drugs was observed with FIC index of 0.443 +/- 0.245, 0.487 +/- 0.247 for isoniazid and 0.468 +/- 0.333, 0.417 +/- 0.345 for rifampicin, whereas EAAS fraction showed partial synergistic effect. A synergistic effect was observed for EAAS fraction and flavanoids sulphates with FIC index < 0.5 with antibiotics. Hemolysis assay on RBCs suggested that EAAS and flavanoids sulphates exhibited least cellular toxicity to erythrocytes as compared to chloramphenicol. In vivo studies in mice infected with K. pneumoniae demonstrated that on day 10 post treatment of different fractions and isolated compounds of A. speciosa, about 60% of the animals treated with EAAS, 70% of animals treated with flavanoids sulphates and 40% of animals treated with EtAS were survived.